碱蓬多酚氧化酶基因的克隆及序列分析

Cloning and sequence analyzing of polyphenol oxidase gene of suaeda salsa

多酚氧化酶（polyphenol oxidase,PPO）是一类植物体内广泛存在的由核基因编码的能与铜结合的金属蛋白酶,是碱蓬甜菜红素合成的第一关键酶。以盘锦红海滩碱蓬（盐地碱蓬）为研究材料,采用同源克隆法,根据植物中已克隆出的PPO序列进行引物设计,利用RT-PCR和RACE技术,从碱蓬中克隆出的PPO基因cDNA全长为1 830 bp,编码609个氨基酸。序列分析表明,与其他植物PPO核苷酸序列的相似性为69%~87%,氨基酸的相似性为49%~62%。碱蓬多酚氧化酶基因的成功克隆,为碱蓬甜菜红素的研究和利用打下了坚实的理论基础。

Polyphenol oxidase （PPO） were metalloproteinase, which were widespread in plants and could combind with copper. It was the most important enzyme for synthesizing betacyanins in Suaeda sa/sa. The red beach Suaeda salsa was taken as the research material, homologous cloning was used to obtain the sequence of the PPO gene in Suaeda salsa. According to the plants that the PPO geue sequences had been cloned and analyzed, primers were designed and RT-PCR and RACE technologies were used to amplify the gene. After sequencing, a segment of 1 830 bp was obtained, and it encoded 690 amino acids. Sequence analysis showed that it had 69%-87% similarity in nucleotides and 49%-62% similarities in amino acids with other plants when compared to them. The successful cloning of PPO gene laid a solid theoretical basis for the future research and utilization of betacyanins in Suaeda salsa.